Joint warfighting doctrine has continued to evolve since World War II, and most recently has become an issue of substantial focus and development within the U.S. military. Today it is recognized that the significance of joint warfighting is its potential for overwhelming effect, in today's terms, the means by which the full measure of U.S. military power can be brought to bear effectively in any crisis. In fully understanding the concept of joint warfighting the first question to ask is what makes joint warfighting joint. The formal answer is found in current doctrine that says that joint warfighting exists when it involves forces of two or more Service departments; they are effective when the unique strengths and advantages of their forces are successfully integrated and focused. It works better than a nonjoint approach, which can be proved through historical analysis. A number of historical examples can illustrate and reinforce the efficacy of joint warfighting. One such example is the Japanese campaign against British Commonwealth forces in Malaya during World War II. During that campaign the Japanese applied the tenets of joint warfare doctrine in defeating the British.